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    <title>expm</title>
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    <center>Scilab Function</center>
    <div align="right">Last update : 16/12/2004</div>
    <p>
      <b>expm</b> -  square matrix exponential</p>
    <h3>
      <font color="blue">Calling Sequence</font>
    </h3>
    <dl>
      <dd>
        <tt>expm(X)  </tt>
      </dd>
    </dl>
    <h3>
      <font color="blue">Parameters</font>
    </h3>
    <ul>
      <li>
        <tt>
          <b>X</b>
        </tt>: square matrix with real or complex entries.</li>
    </ul>
    <h3>
      <font color="blue">Description</font>
    </h3>
    <p>
      <tt>
        <b>X</b>
      </tt> is a square matrix <tt>
        <b>expm(X)</b>
      </tt> is the matrix</p>
    <p>
      <tt>
        <b>expm(X) = I + X + X^2 /2 + ...</b>
      </tt>
    </p>
    <p>
    The computation is performed by first 
    block-diagonalizing <tt>
        <b>X</b>
      </tt> and then applying a Pade approximation 
    on each block.</p>
    <h3>
      <font color="blue">Examples</font>
    </h3>
    <pre>

X=[1 2;3 4]
expm(X)
logm(expm(X))    
 
  </pre>
    <h3>
      <font color="blue">See Also</font>
    </h3>
    <p>
      <a href="../elementary/logm.htm">
        <tt>
          <b>logm</b>
        </tt>
      </a>,&nbsp;&nbsp;<a href="bdiag.htm">
        <tt>
          <b>bdiag</b>
        </tt>
      </a>,&nbsp;&nbsp;<a href="coff.htm">
        <tt>
          <b>coff</b>
        </tt>
      </a>,&nbsp;&nbsp;<a href="../elementary/log.htm">
        <tt>
          <b>log</b>
        </tt>
      </a>,&nbsp;&nbsp;<a href="exp.htm">
        <tt>
          <b>exp</b>
        </tt>
      </a>,&nbsp;&nbsp;</p>
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